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    <title>Document</title>
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    <script>
        let f = function() {
            return 5;
        }

        let f1 = () => 5;
        let sum = (a, b) => a + b;

        [1, 2, 3].map(ele => ele * ele);

        let arr = [1, 2, 3, 4, 5, 6];
        arr.sort((a, b) => b - a);
        console.log(arr);
    </script>
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